1. Field of the Invention
This invention relates generally to a novel thread protector for threaded and other machined surfaces on the ends of the tubular members. In particular, the invention relates to thread protectors adapted for protecting threaded and machined surfaces on the end of oilfield tubular members against corrosion and damage during shipment and handling prior to their being threadedly coupled with other tubular members for use in an oil or gas well.
2. Description of the Prior Art
Thread protectors have been used for many years to protect the ends of tubular members against damage during shipment and during handling on a drilling rig. Such protectors have been provided not only to protect against the corrosive atmosphere and materials which may be present during shipment and at a drilling location but also to protect the threaded and machined surfaces from damage caused by banging one tubular member against another, and the like. Such protectors have typically sealed at the end of the tubular member by butting against a machined surface or feature and likewise have sealed against some feature such as a shoulder or inclined sealing surface inwardly beyond the thread length.
There has developed a need however, for a thread protector which provides environmental and damage protection for a threaded end surface of a tubular member having no feature against which to seal. Thus, it is an object of this invention to provide a thread protector for threaded tubular members which seals the threads and machined surfaces of the tubular members by contacting and sealing against the "as rolled" pipe body axially inwardly beyond the thread length of the threaded surface.
It is a further object of the invention to provide a thread protector which circumferentially seals about a cylindrical machined surface inwardly of the thread length provided on the end of a tubular member.